Kconfig 68 KB

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  1. # x86 configuration
  2. mainmenu "Linux Kernel Configuration for x86"
  3. # Select 32 or 64 bit
  4. config 64BIT
  5. bool "64-bit kernel" if ARCH = "x86"
  6. default ARCH = "x86_64"
  7. ---help---
  8. Say yes to build a 64-bit kernel - formerly known as x86_64
  9. Say no to build a 32-bit kernel - formerly known as i386
  10. config X86_32
  11. def_bool !64BIT
  12. config X86_64
  13. def_bool 64BIT
  14. ### Arch settings
  15. config X86
  16. def_bool y
  17. select HAVE_AOUT if X86_32
  18. select HAVE_READQ
  19. select HAVE_WRITEQ
  20. select HAVE_UNSTABLE_SCHED_CLOCK
  21. select HAVE_IDE
  22. select HAVE_OPROFILE
  23. select HAVE_PERF_EVENTS if (!M386 && !M486)
  24. select HAVE_IOREMAP_PROT
  25. select HAVE_KPROBES
  26. select ARCH_WANT_OPTIONAL_GPIOLIB
  27. select ARCH_WANT_FRAME_POINTERS
  28. select HAVE_DMA_ATTRS
  29. select HAVE_KRETPROBES
  30. select HAVE_OPTPROBES
  31. select HAVE_FTRACE_MCOUNT_RECORD
  32. select HAVE_DYNAMIC_FTRACE
  33. select HAVE_FUNCTION_TRACER
  34. select HAVE_FUNCTION_GRAPH_TRACER
  35. select HAVE_FUNCTION_GRAPH_FP_TEST
  36. select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  37. select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  38. select HAVE_SYSCALL_TRACEPOINTS
  39. select HAVE_KVM
  40. select HAVE_ARCH_KGDB
  41. select HAVE_ARCH_TRACEHOOK
  42. select HAVE_GENERIC_DMA_COHERENT if X86_32
  43. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  44. select USER_STACKTRACE_SUPPORT
  45. select HAVE_REGS_AND_STACK_ACCESS_API
  46. select HAVE_DMA_API_DEBUG
  47. select HAVE_KERNEL_GZIP
  48. select HAVE_KERNEL_BZIP2
  49. select HAVE_KERNEL_LZMA
  50. select HAVE_KERNEL_LZO
  51. select HAVE_HW_BREAKPOINT
  52. select HAVE_MIXED_BREAKPOINTS_REGS
  53. select PERF_EVENTS
  54. select HAVE_PERF_EVENTS_NMI
  55. select ANON_INODES
  56. select HAVE_ARCH_KMEMCHECK
  57. select HAVE_USER_RETURN_NOTIFIER
  58. config INSTRUCTION_DECODER
  59. def_bool (KPROBES || PERF_EVENTS)
  60. config OUTPUT_FORMAT
  61. string
  62. default "elf32-i386" if X86_32
  63. default "elf64-x86-64" if X86_64
  64. config ARCH_DEFCONFIG
  65. string
  66. default "arch/x86/configs/i386_defconfig" if X86_32
  67. default "arch/x86/configs/x86_64_defconfig" if X86_64
  68. config GENERIC_CMOS_UPDATE
  69. def_bool y
  70. config CLOCKSOURCE_WATCHDOG
  71. def_bool y
  72. config GENERIC_CLOCKEVENTS
  73. def_bool y
  74. config GENERIC_CLOCKEVENTS_BROADCAST
  75. def_bool y
  76. depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  77. config LOCKDEP_SUPPORT
  78. def_bool y
  79. config STACKTRACE_SUPPORT
  80. def_bool y
  81. config HAVE_LATENCYTOP_SUPPORT
  82. def_bool y
  83. config MMU
  84. def_bool y
  85. config ZONE_DMA
  86. def_bool y
  87. config SBUS
  88. bool
  89. config NEED_DMA_MAP_STATE
  90. def_bool (X86_64 || DMAR || DMA_API_DEBUG)
  91. config NEED_SG_DMA_LENGTH
  92. def_bool y
  93. config GENERIC_ISA_DMA
  94. def_bool y
  95. config GENERIC_IOMAP
  96. def_bool y
  97. config GENERIC_BUG
  98. def_bool y
  99. depends on BUG
  100. select GENERIC_BUG_RELATIVE_POINTERS if X86_64
  101. config GENERIC_BUG_RELATIVE_POINTERS
  102. bool
  103. config GENERIC_HWEIGHT
  104. def_bool y
  105. config GENERIC_GPIO
  106. bool
  107. config ARCH_MAY_HAVE_PC_FDC
  108. def_bool y
  109. config RWSEM_GENERIC_SPINLOCK
  110. def_bool !X86_XADD
  111. config RWSEM_XCHGADD_ALGORITHM
  112. def_bool X86_XADD
  113. config ARCH_HAS_CPU_IDLE_WAIT
  114. def_bool y
  115. config GENERIC_CALIBRATE_DELAY
  116. def_bool y
  117. config GENERIC_TIME_VSYSCALL
  118. bool
  119. default X86_64
  120. config ARCH_HAS_CPU_RELAX
  121. def_bool y
  122. config ARCH_HAS_DEFAULT_IDLE
  123. def_bool y
  124. config ARCH_HAS_CACHE_LINE_SIZE
  125. def_bool y
  126. config HAVE_SETUP_PER_CPU_AREA
  127. def_bool y
  128. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  129. def_bool y
  130. config NEED_PER_CPU_PAGE_FIRST_CHUNK
  131. def_bool y
  132. config HAVE_CPUMASK_OF_CPU_MAP
  133. def_bool X86_64_SMP
  134. config ARCH_HIBERNATION_POSSIBLE
  135. def_bool y
  136. config ARCH_SUSPEND_POSSIBLE
  137. def_bool y
  138. config ZONE_DMA32
  139. bool
  140. default X86_64
  141. config ARCH_POPULATES_NODE_MAP
  142. def_bool y
  143. config AUDIT_ARCH
  144. bool
  145. default X86_64
  146. config ARCH_SUPPORTS_OPTIMIZED_INLINING
  147. def_bool y
  148. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  149. def_bool y
  150. config HAVE_EARLY_RES
  151. def_bool y
  152. config HAVE_INTEL_TXT
  153. def_bool y
  154. depends on EXPERIMENTAL && DMAR && ACPI
  155. # Use the generic interrupt handling code in kernel/irq/:
  156. config GENERIC_HARDIRQS
  157. def_bool y
  158. config GENERIC_HARDIRQS_NO__DO_IRQ
  159. def_bool y
  160. config GENERIC_IRQ_PROBE
  161. def_bool y
  162. config GENERIC_PENDING_IRQ
  163. def_bool y
  164. depends on GENERIC_HARDIRQS && SMP
  165. config USE_GENERIC_SMP_HELPERS
  166. def_bool y
  167. depends on SMP
  168. config X86_32_SMP
  169. def_bool y
  170. depends on X86_32 && SMP
  171. config X86_64_SMP
  172. def_bool y
  173. depends on X86_64 && SMP
  174. config X86_HT
  175. def_bool y
  176. depends on SMP
  177. config X86_TRAMPOLINE
  178. def_bool y
  179. depends on SMP || (64BIT && ACPI_SLEEP)
  180. config X86_32_LAZY_GS
  181. def_bool y
  182. depends on X86_32 && !CC_STACKPROTECTOR
  183. config ARCH_HWEIGHT_CFLAGS
  184. string
  185. default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
  186. default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
  187. config KTIME_SCALAR
  188. def_bool X86_32
  189. config ARCH_CPU_PROBE_RELEASE
  190. def_bool y
  191. depends on HOTPLUG_CPU
  192. source "init/Kconfig"
  193. source "kernel/Kconfig.freezer"
  194. menu "Processor type and features"
  195. source "kernel/time/Kconfig"
  196. config SMP
  197. bool "Symmetric multi-processing support"
  198. ---help---
  199. This enables support for systems with more than one CPU. If you have
  200. a system with only one CPU, like most personal computers, say N. If
  201. you have a system with more than one CPU, say Y.
  202. If you say N here, the kernel will run on single and multiprocessor
  203. machines, but will use only one CPU of a multiprocessor machine. If
  204. you say Y here, the kernel will run on many, but not all,
  205. singleprocessor machines. On a singleprocessor machine, the kernel
  206. will run faster if you say N here.
  207. Note that if you say Y here and choose architecture "586" or
  208. "Pentium" under "Processor family", the kernel will not work on 486
  209. architectures. Similarly, multiprocessor kernels for the "PPro"
  210. architecture may not work on all Pentium based boards.
  211. People using multiprocessor machines who say Y here should also say
  212. Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
  213. Management" code will be disabled if you say Y here.
  214. See also <file:Documentation/i386/IO-APIC.txt>,
  215. <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
  216. <http://www.tldp.org/docs.html#howto>.
  217. If you don't know what to do here, say N.
  218. config X86_X2APIC
  219. bool "Support x2apic"
  220. depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
  221. ---help---
  222. This enables x2apic support on CPUs that have this feature.
  223. This allows 32-bit apic IDs (so it can support very large systems),
  224. and accesses the local apic via MSRs not via mmio.
  225. If you don't know what to do here, say N.
  226. config SPARSE_IRQ
  227. bool "Support sparse irq numbering"
  228. depends on PCI_MSI || HT_IRQ
  229. ---help---
  230. This enables support for sparse irqs. This is useful for distro
  231. kernels that want to define a high CONFIG_NR_CPUS value but still
  232. want to have low kernel memory footprint on smaller machines.
  233. ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
  234. out the irq_desc[] array in a more NUMA-friendly way. )
  235. If you don't know what to do here, say N.
  236. config NUMA_IRQ_DESC
  237. def_bool y
  238. depends on SPARSE_IRQ && NUMA
  239. config X86_MPPARSE
  240. bool "Enable MPS table" if ACPI
  241. default y
  242. depends on X86_LOCAL_APIC
  243. ---help---
  244. For old smp systems that do not have proper acpi support. Newer systems
  245. (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
  246. config X86_BIGSMP
  247. bool "Support for big SMP systems with more than 8 CPUs"
  248. depends on X86_32 && SMP
  249. ---help---
  250. This option is needed for the systems that have more than 8 CPUs
  251. if X86_32
  252. config X86_EXTENDED_PLATFORM
  253. bool "Support for extended (non-PC) x86 platforms"
  254. default y
  255. ---help---
  256. If you disable this option then the kernel will only support
  257. standard PC platforms. (which covers the vast majority of
  258. systems out there.)
  259. If you enable this option then you'll be able to select support
  260. for the following (non-PC) 32 bit x86 platforms:
  261. AMD Elan
  262. NUMAQ (IBM/Sequent)
  263. RDC R-321x SoC
  264. SGI 320/540 (Visual Workstation)
  265. Summit/EXA (IBM x440)
  266. Unisys ES7000 IA32 series
  267. Moorestown MID devices
  268. If you have one of these systems, or if you want to build a
  269. generic distribution kernel, say Y here - otherwise say N.
  270. endif
  271. if X86_64
  272. config X86_EXTENDED_PLATFORM
  273. bool "Support for extended (non-PC) x86 platforms"
  274. default y
  275. ---help---
  276. If you disable this option then the kernel will only support
  277. standard PC platforms. (which covers the vast majority of
  278. systems out there.)
  279. If you enable this option then you'll be able to select support
  280. for the following (non-PC) 64 bit x86 platforms:
  281. ScaleMP vSMP
  282. SGI Ultraviolet
  283. If you have one of these systems, or if you want to build a
  284. generic distribution kernel, say Y here - otherwise say N.
  285. endif
  286. # This is an alphabetically sorted list of 64 bit extended platforms
  287. # Please maintain the alphabetic order if and when there are additions
  288. config X86_VSMP
  289. bool "ScaleMP vSMP"
  290. select PARAVIRT
  291. depends on X86_64 && PCI
  292. depends on X86_EXTENDED_PLATFORM
  293. ---help---
  294. Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
  295. supposed to run on these EM64T-based machines. Only choose this option
  296. if you have one of these machines.
  297. config X86_UV
  298. bool "SGI Ultraviolet"
  299. depends on X86_64
  300. depends on X86_EXTENDED_PLATFORM
  301. depends on NUMA
  302. depends on X86_X2APIC
  303. ---help---
  304. This option is needed in order to support SGI Ultraviolet systems.
  305. If you don't have one of these, you should say N here.
  306. # Following is an alphabetically sorted list of 32 bit extended platforms
  307. # Please maintain the alphabetic order if and when there are additions
  308. config X86_ELAN
  309. bool "AMD Elan"
  310. depends on X86_32
  311. depends on X86_EXTENDED_PLATFORM
  312. ---help---
  313. Select this for an AMD Elan processor.
  314. Do not use this option for K6/Athlon/Opteron processors!
  315. If unsure, choose "PC-compatible" instead.
  316. config X86_MRST
  317. bool "Moorestown MID platform"
  318. depends on PCI
  319. depends on PCI_GOANY
  320. depends on X86_32
  321. depends on X86_EXTENDED_PLATFORM
  322. depends on X86_IO_APIC
  323. select APB_TIMER
  324. ---help---
  325. Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
  326. Internet Device(MID) platform. Moorestown consists of two chips:
  327. Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
  328. Unlike standard x86 PCs, Moorestown does not have many legacy devices
  329. nor standard legacy replacement devices/features. e.g. Moorestown does
  330. not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
  331. config X86_RDC321X
  332. bool "RDC R-321x SoC"
  333. depends on X86_32
  334. depends on X86_EXTENDED_PLATFORM
  335. select M486
  336. select X86_REBOOTFIXUPS
  337. ---help---
  338. This option is needed for RDC R-321x system-on-chip, also known
  339. as R-8610-(G).
  340. If you don't have one of these chips, you should say N here.
  341. config X86_32_NON_STANDARD
  342. bool "Support non-standard 32-bit SMP architectures"
  343. depends on X86_32 && SMP
  344. depends on X86_EXTENDED_PLATFORM
  345. ---help---
  346. This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
  347. subarchitectures. It is intended for a generic binary kernel.
  348. if you select them all, kernel will probe it one by one. and will
  349. fallback to default.
  350. # Alphabetically sorted list of Non standard 32 bit platforms
  351. config X86_NUMAQ
  352. bool "NUMAQ (IBM/Sequent)"
  353. depends on X86_32_NON_STANDARD
  354. depends on PCI
  355. select NUMA
  356. select X86_MPPARSE
  357. ---help---
  358. This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
  359. NUMA multiquad box. This changes the way that processors are
  360. bootstrapped, and uses Clustered Logical APIC addressing mode instead
  361. of Flat Logical. You will need a new lynxer.elf file to flash your
  362. firmware with - send email to <Martin.Bligh@us.ibm.com>.
  363. config X86_SUPPORTS_MEMORY_FAILURE
  364. def_bool y
  365. # MCE code calls memory_failure():
  366. depends on X86_MCE
  367. # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
  368. depends on !X86_NUMAQ
  369. # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
  370. depends on X86_64 || !SPARSEMEM
  371. select ARCH_SUPPORTS_MEMORY_FAILURE
  372. config X86_VISWS
  373. bool "SGI 320/540 (Visual Workstation)"
  374. depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
  375. depends on X86_32_NON_STANDARD
  376. ---help---
  377. The SGI Visual Workstation series is an IA32-based workstation
  378. based on SGI systems chips with some legacy PC hardware attached.
  379. Say Y here to create a kernel to run on the SGI 320 or 540.
  380. A kernel compiled for the Visual Workstation will run on general
  381. PCs as well. See <file:Documentation/sgi-visws.txt> for details.
  382. config X86_SUMMIT
  383. bool "Summit/EXA (IBM x440)"
  384. depends on X86_32_NON_STANDARD
  385. ---help---
  386. This option is needed for IBM systems that use the Summit/EXA chipset.
  387. In particular, it is needed for the x440.
  388. config X86_ES7000
  389. bool "Unisys ES7000 IA32 series"
  390. depends on X86_32_NON_STANDARD && X86_BIGSMP
  391. ---help---
  392. Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
  393. supposed to run on an IA32-based Unisys ES7000 system.
  394. config SCHED_OMIT_FRAME_POINTER
  395. def_bool y
  396. prompt "Single-depth WCHAN output"
  397. depends on X86
  398. ---help---
  399. Calculate simpler /proc/<PID>/wchan values. If this option
  400. is disabled then wchan values will recurse back to the
  401. caller function. This provides more accurate wchan values,
  402. at the expense of slightly more scheduling overhead.
  403. If in doubt, say "Y".
  404. menuconfig PARAVIRT_GUEST
  405. bool "Paravirtualized guest support"
  406. ---help---
  407. Say Y here to get to see options related to running Linux under
  408. various hypervisors. This option alone does not add any kernel code.
  409. If you say N, all options in this submenu will be skipped and disabled.
  410. if PARAVIRT_GUEST
  411. source "arch/x86/xen/Kconfig"
  412. config VMI
  413. bool "VMI Guest support (DEPRECATED)"
  414. select PARAVIRT
  415. depends on X86_32
  416. ---help---
  417. VMI provides a paravirtualized interface to the VMware ESX server
  418. (it could be used by other hypervisors in theory too, but is not
  419. at the moment), by linking the kernel to a GPL-ed ROM module
  420. provided by the hypervisor.
  421. As of September 2009, VMware has started a phased retirement
  422. of this feature from VMware's products. Please see
  423. feature-removal-schedule.txt for details. If you are
  424. planning to enable this option, please note that you cannot
  425. live migrate a VMI enabled VM to a future VMware product,
  426. which doesn't support VMI. So if you expect your kernel to
  427. seamlessly migrate to newer VMware products, keep this
  428. disabled.
  429. config KVM_CLOCK
  430. bool "KVM paravirtualized clock"
  431. select PARAVIRT
  432. select PARAVIRT_CLOCK
  433. ---help---
  434. Turning on this option will allow you to run a paravirtualized clock
  435. when running over the KVM hypervisor. Instead of relying on a PIT
  436. (or probably other) emulation by the underlying device model, the host
  437. provides the guest with timing infrastructure such as time of day, and
  438. system time
  439. config KVM_GUEST
  440. bool "KVM Guest support"
  441. select PARAVIRT
  442. ---help---
  443. This option enables various optimizations for running under the KVM
  444. hypervisor.
  445. source "arch/x86/lguest/Kconfig"
  446. config PARAVIRT
  447. bool "Enable paravirtualization code"
  448. ---help---
  449. This changes the kernel so it can modify itself when it is run
  450. under a hypervisor, potentially improving performance significantly
  451. over full virtualization. However, when run without a hypervisor
  452. the kernel is theoretically slower and slightly larger.
  453. config PARAVIRT_SPINLOCKS
  454. bool "Paravirtualization layer for spinlocks"
  455. depends on PARAVIRT && SMP && EXPERIMENTAL
  456. ---help---
  457. Paravirtualized spinlocks allow a pvops backend to replace the
  458. spinlock implementation with something virtualization-friendly
  459. (for example, block the virtual CPU rather than spinning).
  460. Unfortunately the downside is an up to 5% performance hit on
  461. native kernels, with various workloads.
  462. If you are unsure how to answer this question, answer N.
  463. config PARAVIRT_CLOCK
  464. bool
  465. endif
  466. config PARAVIRT_DEBUG
  467. bool "paravirt-ops debugging"
  468. depends on PARAVIRT && DEBUG_KERNEL
  469. ---help---
  470. Enable to debug paravirt_ops internals. Specifically, BUG if
  471. a paravirt_op is missing when it is called.
  472. config NO_BOOTMEM
  473. default y
  474. bool "Disable Bootmem code"
  475. ---help---
  476. Use early_res directly instead of bootmem before slab is ready.
  477. - allocator (buddy) [generic]
  478. - early allocator (bootmem) [generic]
  479. - very early allocator (reserve_early*()) [x86]
  480. - very very early allocator (early brk model) [x86]
  481. So reduce one layer between early allocator to final allocator
  482. config MEMTEST
  483. bool "Memtest"
  484. ---help---
  485. This option adds a kernel parameter 'memtest', which allows memtest
  486. to be set.
  487. memtest=0, mean disabled; -- default
  488. memtest=1, mean do 1 test pattern;
  489. ...
  490. memtest=4, mean do 4 test patterns.
  491. If you are unsure how to answer this question, answer N.
  492. config X86_SUMMIT_NUMA
  493. def_bool y
  494. depends on X86_32 && NUMA && X86_32_NON_STANDARD
  495. config X86_CYCLONE_TIMER
  496. def_bool y
  497. depends on X86_32_NON_STANDARD
  498. source "arch/x86/Kconfig.cpu"
  499. config HPET_TIMER
  500. def_bool X86_64
  501. prompt "HPET Timer Support" if X86_32
  502. ---help---
  503. Use the IA-PC HPET (High Precision Event Timer) to manage
  504. time in preference to the PIT and RTC, if a HPET is
  505. present.
  506. HPET is the next generation timer replacing legacy 8254s.
  507. The HPET provides a stable time base on SMP
  508. systems, unlike the TSC, but it is more expensive to access,
  509. as it is off-chip. You can find the HPET spec at
  510. <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
  511. You can safely choose Y here. However, HPET will only be
  512. activated if the platform and the BIOS support this feature.
  513. Otherwise the 8254 will be used for timing services.
  514. Choose N to continue using the legacy 8254 timer.
  515. config HPET_EMULATE_RTC
  516. def_bool y
  517. depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
  518. config APB_TIMER
  519. def_bool y if MRST
  520. prompt "Langwell APB Timer Support" if X86_MRST
  521. help
  522. APB timer is the replacement for 8254, HPET on X86 MID platforms.
  523. The APBT provides a stable time base on SMP
  524. systems, unlike the TSC, but it is more expensive to access,
  525. as it is off-chip. APB timers are always running regardless of CPU
  526. C states, they are used as per CPU clockevent device when possible.
  527. # Mark as embedded because too many people got it wrong.
  528. # The code disables itself when not needed.
  529. config DMI
  530. default y
  531. bool "Enable DMI scanning" if EMBEDDED
  532. ---help---
  533. Enabled scanning of DMI to identify machine quirks. Say Y
  534. here unless you have verified that your setup is not
  535. affected by entries in the DMI blacklist. Required by PNP
  536. BIOS code.
  537. config GART_IOMMU
  538. bool "GART IOMMU support" if EMBEDDED
  539. default y
  540. select SWIOTLB
  541. depends on X86_64 && PCI && K8_NB
  542. ---help---
  543. Support for full DMA access of devices with 32bit memory access only
  544. on systems with more than 3GB. This is usually needed for USB,
  545. sound, many IDE/SATA chipsets and some other devices.
  546. Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
  547. based hardware IOMMU and a software bounce buffer based IOMMU used
  548. on Intel systems and as fallback.
  549. The code is only active when needed (enough memory and limited
  550. device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
  551. too.
  552. config CALGARY_IOMMU
  553. bool "IBM Calgary IOMMU support"
  554. select SWIOTLB
  555. depends on X86_64 && PCI && EXPERIMENTAL
  556. ---help---
  557. Support for hardware IOMMUs in IBM's xSeries x366 and x460
  558. systems. Needed to run systems with more than 3GB of memory
  559. properly with 32-bit PCI devices that do not support DAC
  560. (Double Address Cycle). Calgary also supports bus level
  561. isolation, where all DMAs pass through the IOMMU. This
  562. prevents them from going anywhere except their intended
  563. destination. This catches hard-to-find kernel bugs and
  564. mis-behaving drivers and devices that do not use the DMA-API
  565. properly to set up their DMA buffers. The IOMMU can be
  566. turned off at boot time with the iommu=off parameter.
  567. Normally the kernel will make the right choice by itself.
  568. If unsure, say Y.
  569. config CALGARY_IOMMU_ENABLED_BY_DEFAULT
  570. def_bool y
  571. prompt "Should Calgary be enabled by default?"
  572. depends on CALGARY_IOMMU
  573. ---help---
  574. Should Calgary be enabled by default? if you choose 'y', Calgary
  575. will be used (if it exists). If you choose 'n', Calgary will not be
  576. used even if it exists. If you choose 'n' and would like to use
  577. Calgary anyway, pass 'iommu=calgary' on the kernel command line.
  578. If unsure, say Y.
  579. config AMD_IOMMU
  580. bool "AMD IOMMU support"
  581. select SWIOTLB
  582. select PCI_MSI
  583. depends on X86_64 && PCI && ACPI
  584. ---help---
  585. With this option you can enable support for AMD IOMMU hardware in
  586. your system. An IOMMU is a hardware component which provides
  587. remapping of DMA memory accesses from devices. With an AMD IOMMU you
  588. can isolate the the DMA memory of different devices and protect the
  589. system from misbehaving device drivers or hardware.
  590. You can find out if your system has an AMD IOMMU if you look into
  591. your BIOS for an option to enable it or if you have an IVRS ACPI
  592. table.
  593. config AMD_IOMMU_STATS
  594. bool "Export AMD IOMMU statistics to debugfs"
  595. depends on AMD_IOMMU
  596. select DEBUG_FS
  597. ---help---
  598. This option enables code in the AMD IOMMU driver to collect various
  599. statistics about whats happening in the driver and exports that
  600. information to userspace via debugfs.
  601. If unsure, say N.
  602. # need this always selected by IOMMU for the VIA workaround
  603. config SWIOTLB
  604. def_bool y if X86_64
  605. ---help---
  606. Support for software bounce buffers used on x86-64 systems
  607. which don't have a hardware IOMMU (e.g. the current generation
  608. of Intel's x86-64 CPUs). Using this PCI devices which can only
  609. access 32-bits of memory can be used on systems with more than
  610. 3 GB of memory. If unsure, say Y.
  611. config IOMMU_HELPER
  612. def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
  613. config IOMMU_API
  614. def_bool (AMD_IOMMU || DMAR)
  615. config MAXSMP
  616. bool "Enable Maximum number of SMP Processors and NUMA Nodes"
  617. depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
  618. select CPUMASK_OFFSTACK
  619. ---help---
  620. Enable maximum number of CPUS and NUMA Nodes for this architecture.
  621. If unsure, say N.
  622. config NR_CPUS
  623. int "Maximum number of CPUs" if SMP && !MAXSMP
  624. range 2 8 if SMP && X86_32 && !X86_BIGSMP
  625. range 2 512 if SMP && !MAXSMP
  626. default "1" if !SMP
  627. default "4096" if MAXSMP
  628. default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
  629. default "8" if SMP
  630. ---help---
  631. This allows you to specify the maximum number of CPUs which this
  632. kernel will support. The maximum supported value is 512 and the
  633. minimum value which makes sense is 2.
  634. This is purely to save memory - each supported CPU adds
  635. approximately eight kilobytes to the kernel image.
  636. config SCHED_SMT
  637. bool "SMT (Hyperthreading) scheduler support"
  638. depends on X86_HT
  639. ---help---
  640. SMT scheduler support improves the CPU scheduler's decision making
  641. when dealing with Intel Pentium 4 chips with HyperThreading at a
  642. cost of slightly increased overhead in some places. If unsure say
  643. N here.
  644. config SCHED_MC
  645. def_bool y
  646. prompt "Multi-core scheduler support"
  647. depends on X86_HT
  648. ---help---
  649. Multi-core scheduler support improves the CPU scheduler's decision
  650. making when dealing with multi-core CPU chips at a cost of slightly
  651. increased overhead in some places. If unsure say N here.
  652. source "kernel/Kconfig.preempt"
  653. config X86_UP_APIC
  654. bool "Local APIC support on uniprocessors"
  655. depends on X86_32 && !SMP && !X86_32_NON_STANDARD
  656. ---help---
  657. A local APIC (Advanced Programmable Interrupt Controller) is an
  658. integrated interrupt controller in the CPU. If you have a single-CPU
  659. system which has a processor with a local APIC, you can say Y here to
  660. enable and use it. If you say Y here even though your machine doesn't
  661. have a local APIC, then the kernel will still run with no slowdown at
  662. all. The local APIC supports CPU-generated self-interrupts (timer,
  663. performance counters), and the NMI watchdog which detects hard
  664. lockups.
  665. config X86_UP_IOAPIC
  666. bool "IO-APIC support on uniprocessors"
  667. depends on X86_UP_APIC
  668. ---help---
  669. An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
  670. SMP-capable replacement for PC-style interrupt controllers. Most
  671. SMP systems and many recent uniprocessor systems have one.
  672. If you have a single-CPU system with an IO-APIC, you can say Y here
  673. to use it. If you say Y here even though your machine doesn't have
  674. an IO-APIC, then the kernel will still run with no slowdown at all.
  675. config X86_LOCAL_APIC
  676. def_bool y
  677. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  678. config X86_IO_APIC
  679. def_bool y
  680. depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
  681. config X86_VISWS_APIC
  682. def_bool y
  683. depends on X86_32 && X86_VISWS
  684. config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
  685. bool "Reroute for broken boot IRQs"
  686. depends on X86_IO_APIC
  687. ---help---
  688. This option enables a workaround that fixes a source of
  689. spurious interrupts. This is recommended when threaded
  690. interrupt handling is used on systems where the generation of
  691. superfluous "boot interrupts" cannot be disabled.
  692. Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
  693. entry in the chipset's IO-APIC is masked (as, e.g. the RT
  694. kernel does during interrupt handling). On chipsets where this
  695. boot IRQ generation cannot be disabled, this workaround keeps
  696. the original IRQ line masked so that only the equivalent "boot
  697. IRQ" is delivered to the CPUs. The workaround also tells the
  698. kernel to set up the IRQ handler on the boot IRQ line. In this
  699. way only one interrupt is delivered to the kernel. Otherwise
  700. the spurious second interrupt may cause the kernel to bring
  701. down (vital) interrupt lines.
  702. Only affects "broken" chipsets. Interrupt sharing may be
  703. increased on these systems.
  704. config X86_MCE
  705. bool "Machine Check / overheating reporting"
  706. ---help---
  707. Machine Check support allows the processor to notify the
  708. kernel if it detects a problem (e.g. overheating, data corruption).
  709. The action the kernel takes depends on the severity of the problem,
  710. ranging from warning messages to halting the machine.
  711. config X86_MCE_INTEL
  712. def_bool y
  713. prompt "Intel MCE features"
  714. depends on X86_MCE && X86_LOCAL_APIC
  715. ---help---
  716. Additional support for intel specific MCE features such as
  717. the thermal monitor.
  718. config X86_MCE_AMD
  719. def_bool y
  720. prompt "AMD MCE features"
  721. depends on X86_MCE && X86_LOCAL_APIC
  722. ---help---
  723. Additional support for AMD specific MCE features such as
  724. the DRAM Error Threshold.
  725. config X86_ANCIENT_MCE
  726. bool "Support for old Pentium 5 / WinChip machine checks"
  727. depends on X86_32 && X86_MCE
  728. ---help---
  729. Include support for machine check handling on old Pentium 5 or WinChip
  730. systems. These typically need to be enabled explicitely on the command
  731. line.
  732. config X86_MCE_THRESHOLD
  733. depends on X86_MCE_AMD || X86_MCE_INTEL
  734. def_bool y
  735. config X86_MCE_INJECT
  736. depends on X86_MCE
  737. tristate "Machine check injector support"
  738. ---help---
  739. Provide support for injecting machine checks for testing purposes.
  740. If you don't know what a machine check is and you don't do kernel
  741. QA it is safe to say n.
  742. config X86_THERMAL_VECTOR
  743. def_bool y
  744. depends on X86_MCE_INTEL
  745. config VM86
  746. bool "Enable VM86 support" if EMBEDDED
  747. default y
  748. depends on X86_32
  749. ---help---
  750. This option is required by programs like DOSEMU to run 16-bit legacy
  751. code on X86 processors. It also may be needed by software like
  752. XFree86 to initialize some video cards via BIOS. Disabling this
  753. option saves about 6k.
  754. config TOSHIBA
  755. tristate "Toshiba Laptop support"
  756. depends on X86_32
  757. ---help---
  758. This adds a driver to safely access the System Management Mode of
  759. the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
  760. not work on models with a Phoenix BIOS. The System Management Mode
  761. is used to set the BIOS and power saving options on Toshiba portables.
  762. For information on utilities to make use of this driver see the
  763. Toshiba Linux utilities web site at:
  764. <http://www.buzzard.org.uk/toshiba/>.
  765. Say Y if you intend to run this kernel on a Toshiba portable.
  766. Say N otherwise.
  767. config I8K
  768. tristate "Dell laptop support"
  769. ---help---
  770. This adds a driver to safely access the System Management Mode
  771. of the CPU on the Dell Inspiron 8000. The System Management Mode
  772. is used to read cpu temperature and cooling fan status and to
  773. control the fans on the I8K portables.
  774. This driver has been tested only on the Inspiron 8000 but it may
  775. also work with other Dell laptops. You can force loading on other
  776. models by passing the parameter `force=1' to the module. Use at
  777. your own risk.
  778. For information on utilities to make use of this driver see the
  779. I8K Linux utilities web site at:
  780. <http://people.debian.org/~dz/i8k/>
  781. Say Y if you intend to run this kernel on a Dell Inspiron 8000.
  782. Say N otherwise.
  783. config X86_REBOOTFIXUPS
  784. bool "Enable X86 board specific fixups for reboot"
  785. depends on X86_32
  786. ---help---
  787. This enables chipset and/or board specific fixups to be done
  788. in order to get reboot to work correctly. This is only needed on
  789. some combinations of hardware and BIOS. The symptom, for which
  790. this config is intended, is when reboot ends with a stalled/hung
  791. system.
  792. Currently, the only fixup is for the Geode machines using
  793. CS5530A and CS5536 chipsets and the RDC R-321x SoC.
  794. Say Y if you want to enable the fixup. Currently, it's safe to
  795. enable this option even if you don't need it.
  796. Say N otherwise.
  797. config MICROCODE
  798. tristate "/dev/cpu/microcode - microcode support"
  799. select FW_LOADER
  800. ---help---
  801. If you say Y here, you will be able to update the microcode on
  802. certain Intel and AMD processors. The Intel support is for the
  803. IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
  804. Pentium 4, Xeon etc. The AMD support is for family 0x10 and
  805. 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
  806. You will obviously need the actual microcode binary data itself
  807. which is not shipped with the Linux kernel.
  808. This option selects the general module only, you need to select
  809. at least one vendor specific module as well.
  810. To compile this driver as a module, choose M here: the
  811. module will be called microcode.
  812. config MICROCODE_INTEL
  813. bool "Intel microcode patch loading support"
  814. depends on MICROCODE
  815. default MICROCODE
  816. select FW_LOADER
  817. ---help---
  818. This options enables microcode patch loading support for Intel
  819. processors.
  820. For latest news and information on obtaining all the required
  821. Intel ingredients for this driver, check:
  822. <http://www.urbanmyth.org/microcode/>.
  823. config MICROCODE_AMD
  824. bool "AMD microcode patch loading support"
  825. depends on MICROCODE
  826. select FW_LOADER
  827. ---help---
  828. If you select this option, microcode patch loading support for AMD
  829. processors will be enabled.
  830. config MICROCODE_OLD_INTERFACE
  831. def_bool y
  832. depends on MICROCODE
  833. config X86_MSR
  834. tristate "/dev/cpu/*/msr - Model-specific register support"
  835. ---help---
  836. This device gives privileged processes access to the x86
  837. Model-Specific Registers (MSRs). It is a character device with
  838. major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
  839. MSR accesses are directed to a specific CPU on multi-processor
  840. systems.
  841. config X86_CPUID
  842. tristate "/dev/cpu/*/cpuid - CPU information support"
  843. ---help---
  844. This device gives processes access to the x86 CPUID instruction to
  845. be executed on a specific processor. It is a character device
  846. with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
  847. /dev/cpu/31/cpuid.
  848. choice
  849. prompt "High Memory Support"
  850. default HIGHMEM64G if X86_NUMAQ
  851. default HIGHMEM4G
  852. depends on X86_32
  853. config NOHIGHMEM
  854. bool "off"
  855. depends on !X86_NUMAQ
  856. ---help---
  857. Linux can use up to 64 Gigabytes of physical memory on x86 systems.
  858. However, the address space of 32-bit x86 processors is only 4
  859. Gigabytes large. That means that, if you have a large amount of
  860. physical memory, not all of it can be "permanently mapped" by the
  861. kernel. The physical memory that's not permanently mapped is called
  862. "high memory".
  863. If you are compiling a kernel which will never run on a machine with
  864. more than 1 Gigabyte total physical RAM, answer "off" here (default
  865. choice and suitable for most users). This will result in a "3GB/1GB"
  866. split: 3GB are mapped so that each process sees a 3GB virtual memory
  867. space and the remaining part of the 4GB virtual memory space is used
  868. by the kernel to permanently map as much physical memory as
  869. possible.
  870. If the machine has between 1 and 4 Gigabytes physical RAM, then
  871. answer "4GB" here.
  872. If more than 4 Gigabytes is used then answer "64GB" here. This
  873. selection turns Intel PAE (Physical Address Extension) mode on.
  874. PAE implements 3-level paging on IA32 processors. PAE is fully
  875. supported by Linux, PAE mode is implemented on all recent Intel
  876. processors (Pentium Pro and better). NOTE: If you say "64GB" here,
  877. then the kernel will not boot on CPUs that don't support PAE!
  878. The actual amount of total physical memory will either be
  879. auto detected or can be forced by using a kernel command line option
  880. such as "mem=256M". (Try "man bootparam" or see the documentation of
  881. your boot loader (lilo or loadlin) about how to pass options to the
  882. kernel at boot time.)
  883. If unsure, say "off".
  884. config HIGHMEM4G
  885. bool "4GB"
  886. depends on !X86_NUMAQ
  887. ---help---
  888. Select this if you have a 32-bit processor and between 1 and 4
  889. gigabytes of physical RAM.
  890. config HIGHMEM64G
  891. bool "64GB"
  892. depends on !M386 && !M486
  893. select X86_PAE
  894. ---help---
  895. Select this if you have a 32-bit processor and more than 4
  896. gigabytes of physical RAM.
  897. endchoice
  898. choice
  899. depends on EXPERIMENTAL
  900. prompt "Memory split" if EMBEDDED
  901. default VMSPLIT_3G
  902. depends on X86_32
  903. ---help---
  904. Select the desired split between kernel and user memory.
  905. If the address range available to the kernel is less than the
  906. physical memory installed, the remaining memory will be available
  907. as "high memory". Accessing high memory is a little more costly
  908. than low memory, as it needs to be mapped into the kernel first.
  909. Note that increasing the kernel address space limits the range
  910. available to user programs, making the address space there
  911. tighter. Selecting anything other than the default 3G/1G split
  912. will also likely make your kernel incompatible with binary-only
  913. kernel modules.
  914. If you are not absolutely sure what you are doing, leave this
  915. option alone!
  916. config VMSPLIT_3G
  917. bool "3G/1G user/kernel split"
  918. config VMSPLIT_3G_OPT
  919. depends on !X86_PAE
  920. bool "3G/1G user/kernel split (for full 1G low memory)"
  921. config VMSPLIT_2G
  922. bool "2G/2G user/kernel split"
  923. config VMSPLIT_2G_OPT
  924. depends on !X86_PAE
  925. bool "2G/2G user/kernel split (for full 2G low memory)"
  926. config VMSPLIT_1G
  927. bool "1G/3G user/kernel split"
  928. endchoice
  929. config PAGE_OFFSET
  930. hex
  931. default 0xB0000000 if VMSPLIT_3G_OPT
  932. default 0x80000000 if VMSPLIT_2G
  933. default 0x78000000 if VMSPLIT_2G_OPT
  934. default 0x40000000 if VMSPLIT_1G
  935. default 0xC0000000
  936. depends on X86_32
  937. config HIGHMEM
  938. def_bool y
  939. depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
  940. config X86_PAE
  941. bool "PAE (Physical Address Extension) Support"
  942. depends on X86_32 && !HIGHMEM4G
  943. ---help---
  944. PAE is required for NX support, and furthermore enables
  945. larger swapspace support for non-overcommit purposes. It
  946. has the cost of more pagetable lookup overhead, and also
  947. consumes more pagetable space per process.
  948. config ARCH_PHYS_ADDR_T_64BIT
  949. def_bool X86_64 || X86_PAE
  950. config DIRECT_GBPAGES
  951. bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
  952. default y
  953. depends on X86_64
  954. ---help---
  955. Allow the kernel linear mapping to use 1GB pages on CPUs that
  956. support it. This can improve the kernel's performance a tiny bit by
  957. reducing TLB pressure. If in doubt, say "Y".
  958. # Common NUMA Features
  959. config NUMA
  960. bool "Numa Memory Allocation and Scheduler Support"
  961. depends on SMP
  962. depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
  963. default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
  964. ---help---
  965. Enable NUMA (Non Uniform Memory Access) support.
  966. The kernel will try to allocate memory used by a CPU on the
  967. local memory controller of the CPU and add some more
  968. NUMA awareness to the kernel.
  969. For 64-bit this is recommended if the system is Intel Core i7
  970. (or later), AMD Opteron, or EM64T NUMA.
  971. For 32-bit this is only needed on (rare) 32-bit-only platforms
  972. that support NUMA topologies, such as NUMAQ / Summit, or if you
  973. boot a 32-bit kernel on a 64-bit NUMA platform.
  974. Otherwise, you should say N.
  975. comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
  976. depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
  977. config K8_NUMA
  978. def_bool y
  979. prompt "Old style AMD Opteron NUMA detection"
  980. depends on X86_64 && NUMA && PCI
  981. ---help---
  982. Enable K8 NUMA node topology detection. You should say Y here if
  983. you have a multi processor AMD K8 system. This uses an old
  984. method to read the NUMA configuration directly from the builtin
  985. Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
  986. instead, which also takes priority if both are compiled in.
  987. config X86_64_ACPI_NUMA
  988. def_bool y
  989. prompt "ACPI NUMA detection"
  990. depends on X86_64 && NUMA && ACPI && PCI
  991. select ACPI_NUMA
  992. ---help---
  993. Enable ACPI SRAT based node topology detection.
  994. # Some NUMA nodes have memory ranges that span
  995. # other nodes. Even though a pfn is valid and
  996. # between a node's start and end pfns, it may not
  997. # reside on that node. See memmap_init_zone()
  998. # for details.
  999. config NODES_SPAN_OTHER_NODES
  1000. def_bool y
  1001. depends on X86_64_ACPI_NUMA
  1002. config NUMA_EMU
  1003. bool "NUMA emulation"
  1004. depends on X86_64 && NUMA
  1005. ---help---
  1006. Enable NUMA emulation. A flat machine will be split
  1007. into virtual nodes when booted with "numa=fake=N", where N is the
  1008. number of nodes. This is only useful for debugging.
  1009. config NODES_SHIFT
  1010. int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
  1011. range 1 10
  1012. default "10" if MAXSMP
  1013. default "6" if X86_64
  1014. default "4" if X86_NUMAQ
  1015. default "3"
  1016. depends on NEED_MULTIPLE_NODES
  1017. ---help---
  1018. Specify the maximum number of NUMA Nodes available on the target
  1019. system. Increases memory reserved to accommodate various tables.
  1020. config HAVE_ARCH_BOOTMEM
  1021. def_bool y
  1022. depends on X86_32 && NUMA
  1023. config ARCH_HAVE_MEMORY_PRESENT
  1024. def_bool y
  1025. depends on X86_32 && DISCONTIGMEM
  1026. config NEED_NODE_MEMMAP_SIZE
  1027. def_bool y
  1028. depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
  1029. config HAVE_ARCH_ALLOC_REMAP
  1030. def_bool y
  1031. depends on X86_32 && NUMA
  1032. config ARCH_FLATMEM_ENABLE
  1033. def_bool y
  1034. depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
  1035. config ARCH_DISCONTIGMEM_ENABLE
  1036. def_bool y
  1037. depends on NUMA && X86_32
  1038. config ARCH_DISCONTIGMEM_DEFAULT
  1039. def_bool y
  1040. depends on NUMA && X86_32
  1041. config ARCH_PROC_KCORE_TEXT
  1042. def_bool y
  1043. depends on X86_64 && PROC_KCORE
  1044. config ARCH_SPARSEMEM_DEFAULT
  1045. def_bool y
  1046. depends on X86_64
  1047. config ARCH_SPARSEMEM_ENABLE
  1048. def_bool y
  1049. depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
  1050. select SPARSEMEM_STATIC if X86_32
  1051. select SPARSEMEM_VMEMMAP_ENABLE if X86_64
  1052. config ARCH_SELECT_MEMORY_MODEL
  1053. def_bool y
  1054. depends on ARCH_SPARSEMEM_ENABLE
  1055. config ARCH_MEMORY_PROBE
  1056. def_bool X86_64
  1057. depends on MEMORY_HOTPLUG
  1058. config ILLEGAL_POINTER_VALUE
  1059. hex
  1060. default 0 if X86_32
  1061. default 0xdead000000000000 if X86_64
  1062. source "mm/Kconfig"
  1063. config HIGHPTE
  1064. bool "Allocate 3rd-level pagetables from highmem"
  1065. depends on HIGHMEM
  1066. ---help---
  1067. The VM uses one page table entry for each page of physical memory.
  1068. For systems with a lot of RAM, this can be wasteful of precious
  1069. low memory. Setting this option will put user-space page table
  1070. entries in high memory.
  1071. config X86_CHECK_BIOS_CORRUPTION
  1072. bool "Check for low memory corruption"
  1073. ---help---
  1074. Periodically check for memory corruption in low memory, which
  1075. is suspected to be caused by BIOS. Even when enabled in the
  1076. configuration, it is disabled at runtime. Enable it by
  1077. setting "memory_corruption_check=1" on the kernel command
  1078. line. By default it scans the low 64k of memory every 60
  1079. seconds; see the memory_corruption_check_size and
  1080. memory_corruption_check_period parameters in
  1081. Documentation/kernel-parameters.txt to adjust this.
  1082. When enabled with the default parameters, this option has
  1083. almost no overhead, as it reserves a relatively small amount
  1084. of memory and scans it infrequently. It both detects corruption
  1085. and prevents it from affecting the running system.
  1086. It is, however, intended as a diagnostic tool; if repeatable
  1087. BIOS-originated corruption always affects the same memory,
  1088. you can use memmap= to prevent the kernel from using that
  1089. memory.
  1090. config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
  1091. bool "Set the default setting of memory_corruption_check"
  1092. depends on X86_CHECK_BIOS_CORRUPTION
  1093. default y
  1094. ---help---
  1095. Set whether the default state of memory_corruption_check is
  1096. on or off.
  1097. config X86_RESERVE_LOW_64K
  1098. bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
  1099. default y
  1100. ---help---
  1101. Reserve the first 64K of physical RAM on BIOSes that are known
  1102. to potentially corrupt that memory range. A numbers of BIOSes are
  1103. known to utilize this area during suspend/resume, so it must not
  1104. be used by the kernel.
  1105. Set this to N if you are absolutely sure that you trust the BIOS
  1106. to get all its memory reservations and usages right.
  1107. If you have doubts about the BIOS (e.g. suspend/resume does not
  1108. work or there's kernel crashes after certain hardware hotplug
  1109. events) and it's not AMI or Phoenix, then you might want to enable
  1110. X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
  1111. corruption patterns.
  1112. Say Y if unsure.
  1113. config MATH_EMULATION
  1114. bool
  1115. prompt "Math emulation" if X86_32
  1116. ---help---
  1117. Linux can emulate a math coprocessor (used for floating point
  1118. operations) if you don't have one. 486DX and Pentium processors have
  1119. a math coprocessor built in, 486SX and 386 do not, unless you added
  1120. a 487DX or 387, respectively. (The messages during boot time can
  1121. give you some hints here ["man dmesg"].) Everyone needs either a
  1122. coprocessor or this emulation.
  1123. If you don't have a math coprocessor, you need to say Y here; if you
  1124. say Y here even though you have a coprocessor, the coprocessor will
  1125. be used nevertheless. (This behavior can be changed with the kernel
  1126. command line option "no387", which comes handy if your coprocessor
  1127. is broken. Try "man bootparam" or see the documentation of your boot
  1128. loader (lilo or loadlin) about how to pass options to the kernel at
  1129. boot time.) This means that it is a good idea to say Y here if you
  1130. intend to use this kernel on different machines.
  1131. More information about the internals of the Linux math coprocessor
  1132. emulation can be found in <file:arch/x86/math-emu/README>.
  1133. If you are not sure, say Y; apart from resulting in a 66 KB bigger
  1134. kernel, it won't hurt.
  1135. config MTRR
  1136. def_bool y
  1137. prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
  1138. ---help---
  1139. On Intel P6 family processors (Pentium Pro, Pentium II and later)
  1140. the Memory Type Range Registers (MTRRs) may be used to control
  1141. processor access to memory ranges. This is most useful if you have
  1142. a video (VGA) card on a PCI or AGP bus. Enabling write-combining
  1143. allows bus write transfers to be combined into a larger transfer
  1144. before bursting over the PCI/AGP bus. This can increase performance
  1145. of image write operations 2.5 times or more. Saying Y here creates a
  1146. /proc/mtrr file which may be used to manipulate your processor's
  1147. MTRRs. Typically the X server should use this.
  1148. This code has a reasonably generic interface so that similar
  1149. control registers on other processors can be easily supported
  1150. as well:
  1151. The Cyrix 6x86, 6x86MX and M II processors have Address Range
  1152. Registers (ARRs) which provide a similar functionality to MTRRs. For
  1153. these, the ARRs are used to emulate the MTRRs.
  1154. The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
  1155. MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
  1156. write-combining. All of these processors are supported by this code
  1157. and it makes sense to say Y here if you have one of them.
  1158. Saying Y here also fixes a problem with buggy SMP BIOSes which only
  1159. set the MTRRs for the boot CPU and not for the secondary CPUs. This
  1160. can lead to all sorts of problems, so it's good to say Y here.
  1161. You can safely say Y even if your machine doesn't have MTRRs, you'll
  1162. just add about 9 KB to your kernel.
  1163. See <file:Documentation/x86/mtrr.txt> for more information.
  1164. config MTRR_SANITIZER
  1165. def_bool y
  1166. prompt "MTRR cleanup support"
  1167. depends on MTRR
  1168. ---help---
  1169. Convert MTRR layout from continuous to discrete, so X drivers can
  1170. add writeback entries.
  1171. Can be disabled with disable_mtrr_cleanup on the kernel command line.
  1172. The largest mtrr entry size for a continuous block can be set with
  1173. mtrr_chunk_size.
  1174. If unsure, say Y.
  1175. config MTRR_SANITIZER_ENABLE_DEFAULT
  1176. int "MTRR cleanup enable value (0-1)"
  1177. range 0 1
  1178. default "0"
  1179. depends on MTRR_SANITIZER
  1180. ---help---
  1181. Enable mtrr cleanup default value
  1182. config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
  1183. int "MTRR cleanup spare reg num (0-7)"
  1184. range 0 7
  1185. default "1"
  1186. depends on MTRR_SANITIZER
  1187. ---help---
  1188. mtrr cleanup spare entries default, it can be changed via
  1189. mtrr_spare_reg_nr=N on the kernel command line.
  1190. config X86_PAT
  1191. def_bool y
  1192. prompt "x86 PAT support" if EMBEDDED
  1193. depends on MTRR
  1194. ---help---
  1195. Use PAT attributes to setup page level cache control.
  1196. PATs are the modern equivalents of MTRRs and are much more
  1197. flexible than MTRRs.
  1198. Say N here if you see bootup problems (boot crash, boot hang,
  1199. spontaneous reboots) or a non-working video driver.
  1200. If unsure, say Y.
  1201. config ARCH_USES_PG_UNCACHED
  1202. def_bool y
  1203. depends on X86_PAT
  1204. config EFI
  1205. bool "EFI runtime service support"
  1206. depends on ACPI
  1207. ---help---
  1208. This enables the kernel to use EFI runtime services that are
  1209. available (such as the EFI variable services).
  1210. This option is only useful on systems that have EFI firmware.
  1211. In addition, you should use the latest ELILO loader available
  1212. at <http://elilo.sourceforge.net> in order to take advantage
  1213. of EFI runtime services. However, even with this option, the
  1214. resultant kernel should continue to boot on existing non-EFI
  1215. platforms.
  1216. config SECCOMP
  1217. def_bool y
  1218. prompt "Enable seccomp to safely compute untrusted bytecode"
  1219. ---help---
  1220. This kernel feature is useful for number crunching applications
  1221. that may need to compute untrusted bytecode during their
  1222. execution. By using pipes or other transports made available to
  1223. the process as file descriptors supporting the read/write
  1224. syscalls, it's possible to isolate those applications in
  1225. their own address space using seccomp. Once seccomp is
  1226. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  1227. and the task is only allowed to execute a few safe syscalls
  1228. defined by each seccomp mode.
  1229. If unsure, say Y. Only embedded should say N here.
  1230. config CC_STACKPROTECTOR
  1231. bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
  1232. ---help---
  1233. This option turns on the -fstack-protector GCC feature. This
  1234. feature puts, at the beginning of functions, a canary value on
  1235. the stack just before the return address, and validates
  1236. the value just before actually returning. Stack based buffer
  1237. overflows (that need to overwrite this return address) now also
  1238. overwrite the canary, which gets detected and the attack is then
  1239. neutralized via a kernel panic.
  1240. This feature requires gcc version 4.2 or above, or a distribution
  1241. gcc with the feature backported. Older versions are automatically
  1242. detected and for those versions, this configuration option is
  1243. ignored. (and a warning is printed during bootup)
  1244. source kernel/Kconfig.hz
  1245. config KEXEC
  1246. bool "kexec system call"
  1247. ---help---
  1248. kexec is a system call that implements the ability to shutdown your
  1249. current kernel, and to start another kernel. It is like a reboot
  1250. but it is independent of the system firmware. And like a reboot
  1251. you can start any kernel with it, not just Linux.
  1252. The name comes from the similarity to the exec system call.
  1253. It is an ongoing process to be certain the hardware in a machine
  1254. is properly shutdown, so do not be surprised if this code does not
  1255. initially work for you. It may help to enable device hotplugging
  1256. support. As of this writing the exact hardware interface is
  1257. strongly in flux, so no good recommendation can be made.
  1258. config CRASH_DUMP
  1259. bool "kernel crash dumps"
  1260. depends on X86_64 || (X86_32 && HIGHMEM)
  1261. ---help---
  1262. Generate crash dump after being started by kexec.
  1263. This should be normally only set in special crash dump kernels
  1264. which are loaded in the main kernel with kexec-tools into
  1265. a specially reserved region and then later executed after
  1266. a crash by kdump/kexec. The crash dump kernel must be compiled
  1267. to a memory address not used by the main kernel or BIOS using
  1268. PHYSICAL_START, or it must be built as a relocatable image
  1269. (CONFIG_RELOCATABLE=y).
  1270. For more details see Documentation/kdump/kdump.txt
  1271. config KEXEC_JUMP
  1272. bool "kexec jump (EXPERIMENTAL)"
  1273. depends on EXPERIMENTAL
  1274. depends on KEXEC && HIBERNATION
  1275. ---help---
  1276. Jump between original kernel and kexeced kernel and invoke
  1277. code in physical address mode via KEXEC
  1278. config PHYSICAL_START
  1279. hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
  1280. default "0x1000000"
  1281. ---help---
  1282. This gives the physical address where the kernel is loaded.
  1283. If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
  1284. bzImage will decompress itself to above physical address and
  1285. run from there. Otherwise, bzImage will run from the address where
  1286. it has been loaded by the boot loader and will ignore above physical
  1287. address.
  1288. In normal kdump cases one does not have to set/change this option
  1289. as now bzImage can be compiled as a completely relocatable image
  1290. (CONFIG_RELOCATABLE=y) and be used to load and run from a different
  1291. address. This option is mainly useful for the folks who don't want
  1292. to use a bzImage for capturing the crash dump and want to use a
  1293. vmlinux instead. vmlinux is not relocatable hence a kernel needs
  1294. to be specifically compiled to run from a specific memory area
  1295. (normally a reserved region) and this option comes handy.
  1296. So if you are using bzImage for capturing the crash dump,
  1297. leave the value here unchanged to 0x1000000 and set
  1298. CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
  1299. for capturing the crash dump change this value to start of
  1300. the reserved region. In other words, it can be set based on
  1301. the "X" value as specified in the "crashkernel=YM@XM"
  1302. command line boot parameter passed to the panic-ed
  1303. kernel. Please take a look at Documentation/kdump/kdump.txt
  1304. for more details about crash dumps.
  1305. Usage of bzImage for capturing the crash dump is recommended as
  1306. one does not have to build two kernels. Same kernel can be used
  1307. as production kernel and capture kernel. Above option should have
  1308. gone away after relocatable bzImage support is introduced. But it
  1309. is present because there are users out there who continue to use
  1310. vmlinux for dump capture. This option should go away down the
  1311. line.
  1312. Don't change this unless you know what you are doing.
  1313. config RELOCATABLE
  1314. bool "Build a relocatable kernel"
  1315. default y
  1316. ---help---
  1317. This builds a kernel image that retains relocation information
  1318. so it can be loaded someplace besides the default 1MB.
  1319. The relocations tend to make the kernel binary about 10% larger,
  1320. but are discarded at runtime.
  1321. One use is for the kexec on panic case where the recovery kernel
  1322. must live at a different physical address than the primary
  1323. kernel.
  1324. Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
  1325. it has been loaded at and the compile time physical address
  1326. (CONFIG_PHYSICAL_START) is ignored.
  1327. # Relocation on x86-32 needs some additional build support
  1328. config X86_NEED_RELOCS
  1329. def_bool y
  1330. depends on X86_32 && RELOCATABLE
  1331. config PHYSICAL_ALIGN
  1332. hex "Alignment value to which kernel should be aligned" if X86_32
  1333. default "0x1000000"
  1334. range 0x2000 0x1000000
  1335. ---help---
  1336. This value puts the alignment restrictions on physical address
  1337. where kernel is loaded and run from. Kernel is compiled for an
  1338. address which meets above alignment restriction.
  1339. If bootloader loads the kernel at a non-aligned address and
  1340. CONFIG_RELOCATABLE is set, kernel will move itself to nearest
  1341. address aligned to above value and run from there.
  1342. If bootloader loads the kernel at a non-aligned address and
  1343. CONFIG_RELOCATABLE is not set, kernel will ignore the run time
  1344. load address and decompress itself to the address it has been
  1345. compiled for and run from there. The address for which kernel is
  1346. compiled already meets above alignment restrictions. Hence the
  1347. end result is that kernel runs from a physical address meeting
  1348. above alignment restrictions.
  1349. Don't change this unless you know what you are doing.
  1350. config HOTPLUG_CPU
  1351. bool "Support for hot-pluggable CPUs"
  1352. depends on SMP && HOTPLUG
  1353. ---help---
  1354. Say Y here to allow turning CPUs off and on. CPUs can be
  1355. controlled through /sys/devices/system/cpu.
  1356. ( Note: power management support will enable this option
  1357. automatically on SMP systems. )
  1358. Say N if you want to disable CPU hotplug.
  1359. config COMPAT_VDSO
  1360. def_bool y
  1361. prompt "Compat VDSO support"
  1362. depends on X86_32 || IA32_EMULATION
  1363. ---help---
  1364. Map the 32-bit VDSO to the predictable old-style address too.
  1365. Say N here if you are running a sufficiently recent glibc
  1366. version (2.3.3 or later), to remove the high-mapped
  1367. VDSO mapping and to exclusively use the randomized VDSO.
  1368. If unsure, say Y.
  1369. config CMDLINE_BOOL
  1370. bool "Built-in kernel command line"
  1371. ---help---
  1372. Allow for specifying boot arguments to the kernel at
  1373. build time. On some systems (e.g. embedded ones), it is
  1374. necessary or convenient to provide some or all of the
  1375. kernel boot arguments with the kernel itself (that is,
  1376. to not rely on the boot loader to provide them.)
  1377. To compile command line arguments into the kernel,
  1378. set this option to 'Y', then fill in the
  1379. the boot arguments in CONFIG_CMDLINE.
  1380. Systems with fully functional boot loaders (i.e. non-embedded)
  1381. should leave this option set to 'N'.
  1382. config CMDLINE
  1383. string "Built-in kernel command string"
  1384. depends on CMDLINE_BOOL
  1385. default ""
  1386. ---help---
  1387. Enter arguments here that should be compiled into the kernel
  1388. image and used at boot time. If the boot loader provides a
  1389. command line at boot time, it is appended to this string to
  1390. form the full kernel command line, when the system boots.
  1391. However, you can use the CONFIG_CMDLINE_OVERRIDE option to
  1392. change this behavior.
  1393. In most cases, the command line (whether built-in or provided
  1394. by the boot loader) should specify the device for the root
  1395. file system.
  1396. config CMDLINE_OVERRIDE
  1397. bool "Built-in command line overrides boot loader arguments"
  1398. depends on CMDLINE_BOOL
  1399. ---help---
  1400. Set this option to 'Y' to have the kernel ignore the boot loader
  1401. command line, and use ONLY the built-in command line.
  1402. This is used to work around broken boot loaders. This should
  1403. be set to 'N' under normal conditions.
  1404. endmenu
  1405. config ARCH_ENABLE_MEMORY_HOTPLUG
  1406. def_bool y
  1407. depends on X86_64 || (X86_32 && HIGHMEM)
  1408. config ARCH_ENABLE_MEMORY_HOTREMOVE
  1409. def_bool y
  1410. depends on MEMORY_HOTPLUG
  1411. config HAVE_ARCH_EARLY_PFN_TO_NID
  1412. def_bool X86_64
  1413. depends on NUMA
  1414. config USE_PERCPU_NUMA_NODE_ID
  1415. def_bool X86_64
  1416. depends on NUMA
  1417. menu "Power management and ACPI options"
  1418. config ARCH_HIBERNATION_HEADER
  1419. def_bool y
  1420. depends on X86_64 && HIBERNATION
  1421. source "kernel/power/Kconfig"
  1422. source "drivers/acpi/Kconfig"
  1423. source "drivers/sfi/Kconfig"
  1424. config X86_APM_BOOT
  1425. def_bool y
  1426. depends on APM || APM_MODULE
  1427. menuconfig APM
  1428. tristate "APM (Advanced Power Management) BIOS support"
  1429. depends on X86_32 && PM_SLEEP
  1430. ---help---
  1431. APM is a BIOS specification for saving power using several different
  1432. techniques. This is mostly useful for battery powered laptops with
  1433. APM compliant BIOSes. If you say Y here, the system time will be
  1434. reset after a RESUME operation, the /proc/apm device will provide
  1435. battery status information, and user-space programs will receive
  1436. notification of APM "events" (e.g. battery status change).
  1437. If you select "Y" here, you can disable actual use of the APM
  1438. BIOS by passing the "apm=off" option to the kernel at boot time.
  1439. Note that the APM support is almost completely disabled for
  1440. machines with more than one CPU.
  1441. In order to use APM, you will need supporting software. For location
  1442. and more information, read <file:Documentation/power/pm.txt> and the
  1443. Battery Powered Linux mini-HOWTO, available from
  1444. <http://www.tldp.org/docs.html#howto>.
  1445. This driver does not spin down disk drives (see the hdparm(8)
  1446. manpage ("man 8 hdparm") for that), and it doesn't turn off
  1447. VESA-compliant "green" monitors.
  1448. This driver does not support the TI 4000M TravelMate and the ACER
  1449. 486/DX4/75 because they don't have compliant BIOSes. Many "green"
  1450. desktop machines also don't have compliant BIOSes, and this driver
  1451. may cause those machines to panic during the boot phase.
  1452. Generally, if you don't have a battery in your machine, there isn't
  1453. much point in using this driver and you should say N. If you get
  1454. random kernel OOPSes or reboots that don't seem to be related to
  1455. anything, try disabling/enabling this option (or disabling/enabling
  1456. APM in your BIOS).
  1457. Some other things you should try when experiencing seemingly random,
  1458. "weird" problems:
  1459. 1) make sure that you have enough swap space and that it is
  1460. enabled.
  1461. 2) pass the "no-hlt" option to the kernel
  1462. 3) switch on floating point emulation in the kernel and pass
  1463. the "no387" option to the kernel
  1464. 4) pass the "floppy=nodma" option to the kernel
  1465. 5) pass the "mem=4M" option to the kernel (thereby disabling
  1466. all but the first 4 MB of RAM)
  1467. 6) make sure that the CPU is not over clocked.
  1468. 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
  1469. 8) disable the cache from your BIOS settings
  1470. 9) install a fan for the video card or exchange video RAM
  1471. 10) install a better fan for the CPU
  1472. 11) exchange RAM chips
  1473. 12) exchange the motherboard.
  1474. To compile this driver as a module, choose M here: the
  1475. module will be called apm.
  1476. if APM
  1477. config APM_IGNORE_USER_SUSPEND
  1478. bool "Ignore USER SUSPEND"
  1479. ---help---
  1480. This option will ignore USER SUSPEND requests. On machines with a
  1481. compliant APM BIOS, you want to say N. However, on the NEC Versa M
  1482. series notebooks, it is necessary to say Y because of a BIOS bug.
  1483. config APM_DO_ENABLE
  1484. bool "Enable PM at boot time"
  1485. ---help---
  1486. Enable APM features at boot time. From page 36 of the APM BIOS
  1487. specification: "When disabled, the APM BIOS does not automatically
  1488. power manage devices, enter the Standby State, enter the Suspend
  1489. State, or take power saving steps in response to CPU Idle calls."
  1490. This driver will make CPU Idle calls when Linux is idle (unless this
  1491. feature is turned off -- see "Do CPU IDLE calls", below). This
  1492. should always save battery power, but more complicated APM features
  1493. will be dependent on your BIOS implementation. You may need to turn
  1494. this option off if your computer hangs at boot time when using APM
  1495. support, or if it beeps continuously instead of suspending. Turn
  1496. this off if you have a NEC UltraLite Versa 33/C or a Toshiba
  1497. T400CDT. This is off by default since most machines do fine without
  1498. this feature.
  1499. config APM_CPU_IDLE
  1500. bool "Make CPU Idle calls when idle"
  1501. ---help---
  1502. Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
  1503. On some machines, this can activate improved power savings, such as
  1504. a slowed CPU clock rate, when the machine is idle. These idle calls
  1505. are made after the idle loop has run for some length of time (e.g.,
  1506. 333 mS). On some machines, this will cause a hang at boot time or
  1507. whenever the CPU becomes idle. (On machines with more than one CPU,
  1508. this option does nothing.)
  1509. config APM_DISPLAY_BLANK
  1510. bool "Enable console blanking using APM"
  1511. ---help---
  1512. Enable console blanking using the APM. Some laptops can use this to
  1513. turn off the LCD backlight when the screen blanker of the Linux
  1514. virtual console blanks the screen. Note that this is only used by
  1515. the virtual console screen blanker, and won't turn off the backlight
  1516. when using the X Window system. This also doesn't have anything to
  1517. do with your VESA-compliant power-saving monitor. Further, this
  1518. option doesn't work for all laptops -- it might not turn off your
  1519. backlight at all, or it might print a lot of errors to the console,
  1520. especially if you are using gpm.
  1521. config APM_ALLOW_INTS
  1522. bool "Allow interrupts during APM BIOS calls"
  1523. ---help---
  1524. Normally we disable external interrupts while we are making calls to
  1525. the APM BIOS as a measure to lessen the effects of a badly behaving
  1526. BIOS implementation. The BIOS should reenable interrupts if it
  1527. needs to. Unfortunately, some BIOSes do not -- especially those in
  1528. many of the newer IBM Thinkpads. If you experience hangs when you
  1529. suspend, try setting this to Y. Otherwise, say N.
  1530. endif # APM
  1531. source "arch/x86/kernel/cpu/cpufreq/Kconfig"
  1532. source "drivers/cpuidle/Kconfig"
  1533. source "drivers/idle/Kconfig"
  1534. endmenu
  1535. menu "Bus options (PCI etc.)"
  1536. config PCI
  1537. bool "PCI support"
  1538. default y
  1539. select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
  1540. ---help---
  1541. Find out whether you have a PCI motherboard. PCI is the name of a
  1542. bus system, i.e. the way the CPU talks to the other stuff inside
  1543. your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
  1544. VESA. If you have PCI, say Y, otherwise N.
  1545. choice
  1546. prompt "PCI access mode"
  1547. depends on X86_32 && PCI
  1548. default PCI_GOANY
  1549. ---help---
  1550. On PCI systems, the BIOS can be used to detect the PCI devices and
  1551. determine their configuration. However, some old PCI motherboards
  1552. have BIOS bugs and may crash if this is done. Also, some embedded
  1553. PCI-based systems don't have any BIOS at all. Linux can also try to
  1554. detect the PCI hardware directly without using the BIOS.
  1555. With this option, you can specify how Linux should detect the
  1556. PCI devices. If you choose "BIOS", the BIOS will be used,
  1557. if you choose "Direct", the BIOS won't be used, and if you
  1558. choose "MMConfig", then PCI Express MMCONFIG will be used.
  1559. If you choose "Any", the kernel will try MMCONFIG, then the
  1560. direct access method and falls back to the BIOS if that doesn't
  1561. work. If unsure, go with the default, which is "Any".
  1562. config PCI_GOBIOS
  1563. bool "BIOS"
  1564. config PCI_GOMMCONFIG
  1565. bool "MMConfig"
  1566. config PCI_GODIRECT
  1567. bool "Direct"
  1568. config PCI_GOOLPC
  1569. bool "OLPC"
  1570. depends on OLPC
  1571. config PCI_GOANY
  1572. bool "Any"
  1573. endchoice
  1574. config PCI_BIOS
  1575. def_bool y
  1576. depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
  1577. # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
  1578. config PCI_DIRECT
  1579. def_bool y
  1580. depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
  1581. config PCI_MMCONFIG
  1582. def_bool y
  1583. depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
  1584. config PCI_OLPC
  1585. def_bool y
  1586. depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
  1587. config PCI_DOMAINS
  1588. def_bool y
  1589. depends on PCI
  1590. config PCI_MMCONFIG
  1591. bool "Support mmconfig PCI config space access"
  1592. depends on X86_64 && PCI && ACPI
  1593. config PCI_CNB20LE_QUIRK
  1594. bool "Read CNB20LE Host Bridge Windows"
  1595. depends on PCI
  1596. help
  1597. Read the PCI windows out of the CNB20LE host bridge. This allows
  1598. PCI hotplug to work on systems with the CNB20LE chipset which do
  1599. not have ACPI.
  1600. config DMAR
  1601. bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
  1602. depends on PCI_MSI && ACPI && EXPERIMENTAL
  1603. help
  1604. DMA remapping (DMAR) devices support enables independent address
  1605. translations for Direct Memory Access (DMA) from devices.
  1606. These DMA remapping devices are reported via ACPI tables
  1607. and include PCI device scope covered by these DMA
  1608. remapping devices.
  1609. config DMAR_DEFAULT_ON
  1610. def_bool y
  1611. prompt "Enable DMA Remapping Devices by default"
  1612. depends on DMAR
  1613. help
  1614. Selecting this option will enable a DMAR device at boot time if
  1615. one is found. If this option is not selected, DMAR support can
  1616. be enabled by passing intel_iommu=on to the kernel. It is
  1617. recommended you say N here while the DMAR code remains
  1618. experimental.
  1619. config DMAR_BROKEN_GFX_WA
  1620. bool "Workaround broken graphics drivers (going away soon)"
  1621. depends on DMAR && BROKEN
  1622. ---help---
  1623. Current Graphics drivers tend to use physical address
  1624. for DMA and avoid using DMA APIs. Setting this config
  1625. option permits the IOMMU driver to set a unity map for
  1626. all the OS-visible memory. Hence the driver can continue
  1627. to use physical addresses for DMA, at least until this
  1628. option is removed in the 2.6.32 kernel.
  1629. config DMAR_FLOPPY_WA
  1630. def_bool y
  1631. depends on DMAR
  1632. ---help---
  1633. Floppy disk drivers are known to bypass DMA API calls
  1634. thereby failing to work when IOMMU is enabled. This
  1635. workaround will setup a 1:1 mapping for the first
  1636. 16MiB to make floppy (an ISA device) work.
  1637. config INTR_REMAP
  1638. bool "Support for Interrupt Remapping (EXPERIMENTAL)"
  1639. depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
  1640. ---help---
  1641. Supports Interrupt remapping for IO-APIC and MSI devices.
  1642. To use x2apic mode in the CPU's which support x2APIC enhancements or
  1643. to support platforms with CPU's having > 8 bit APIC ID, say Y.
  1644. source "drivers/pci/pcie/Kconfig"
  1645. source "drivers/pci/Kconfig"
  1646. # x86_64 have no ISA slots, but do have ISA-style DMA.
  1647. config ISA_DMA_API
  1648. def_bool y
  1649. if X86_32
  1650. config ISA
  1651. bool "ISA support"
  1652. ---help---
  1653. Find out whether you have ISA slots on your motherboard. ISA is the
  1654. name of a bus system, i.e. the way the CPU talks to the other stuff
  1655. inside your box. Other bus systems are PCI, EISA, MicroChannel
  1656. (MCA) or VESA. ISA is an older system, now being displaced by PCI;
  1657. newer boards don't support it. If you have ISA, say Y, otherwise N.
  1658. config EISA
  1659. bool "EISA support"
  1660. depends on ISA
  1661. ---help---
  1662. The Extended Industry Standard Architecture (EISA) bus was
  1663. developed as an open alternative to the IBM MicroChannel bus.
  1664. The EISA bus provided some of the features of the IBM MicroChannel
  1665. bus while maintaining backward compatibility with cards made for
  1666. the older ISA bus. The EISA bus saw limited use between 1988 and
  1667. 1995 when it was made obsolete by the PCI bus.
  1668. Say Y here if you are building a kernel for an EISA-based machine.
  1669. Otherwise, say N.
  1670. source "drivers/eisa/Kconfig"
  1671. config MCA
  1672. bool "MCA support"
  1673. ---help---
  1674. MicroChannel Architecture is found in some IBM PS/2 machines and
  1675. laptops. It is a bus system similar to PCI or ISA. See
  1676. <file:Documentation/mca.txt> (and especially the web page given
  1677. there) before attempting to build an MCA bus kernel.
  1678. source "drivers/mca/Kconfig"
  1679. config SCx200
  1680. tristate "NatSemi SCx200 support"
  1681. ---help---
  1682. This provides basic support for National Semiconductor's
  1683. (now AMD's) Geode processors. The driver probes for the
  1684. PCI-IDs of several on-chip devices, so its a good dependency
  1685. for other scx200_* drivers.
  1686. If compiled as a module, the driver is named scx200.
  1687. config SCx200HR_TIMER
  1688. tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
  1689. depends on SCx200
  1690. default y
  1691. ---help---
  1692. This driver provides a clocksource built upon the on-chip
  1693. 27MHz high-resolution timer. Its also a workaround for
  1694. NSC Geode SC-1100's buggy TSC, which loses time when the
  1695. processor goes idle (as is done by the scheduler). The
  1696. other workaround is idle=poll boot option.
  1697. config OLPC
  1698. bool "One Laptop Per Child support"
  1699. select GPIOLIB
  1700. ---help---
  1701. Add support for detecting the unique features of the OLPC
  1702. XO hardware.
  1703. config OLPC_OPENFIRMWARE
  1704. bool "Support for OLPC's Open Firmware"
  1705. depends on !X86_64 && !X86_PAE
  1706. default y if OLPC
  1707. help
  1708. This option adds support for the implementation of Open Firmware
  1709. that is used on the OLPC XO-1 Children's Machine.
  1710. If unsure, say N here.
  1711. endif # X86_32
  1712. config K8_NB
  1713. def_bool y
  1714. depends on CPU_SUP_AMD && PCI
  1715. source "drivers/pcmcia/Kconfig"
  1716. source "drivers/pci/hotplug/Kconfig"
  1717. endmenu
  1718. menu "Executable file formats / Emulations"
  1719. source "fs/Kconfig.binfmt"
  1720. config IA32_EMULATION
  1721. bool "IA32 Emulation"
  1722. depends on X86_64
  1723. select COMPAT_BINFMT_ELF
  1724. ---help---
  1725. Include code to run 32-bit programs under a 64-bit kernel. You should
  1726. likely turn this on, unless you're 100% sure that you don't have any
  1727. 32-bit programs left.
  1728. config IA32_AOUT
  1729. tristate "IA32 a.out support"
  1730. depends on IA32_EMULATION
  1731. ---help---
  1732. Support old a.out binaries in the 32bit emulation.
  1733. config COMPAT
  1734. def_bool y
  1735. depends on IA32_EMULATION
  1736. config COMPAT_FOR_U64_ALIGNMENT
  1737. def_bool COMPAT
  1738. depends on X86_64
  1739. config SYSVIPC_COMPAT
  1740. def_bool y
  1741. depends on COMPAT && SYSVIPC
  1742. endmenu
  1743. config HAVE_ATOMIC_IOMAP
  1744. def_bool y
  1745. depends on X86_32
  1746. source "net/Kconfig"
  1747. source "drivers/Kconfig"
  1748. source "drivers/firmware/Kconfig"
  1749. source "fs/Kconfig"
  1750. source "arch/x86/Kconfig.debug"
  1751. source "security/Kconfig"
  1752. source "crypto/Kconfig"
  1753. source "arch/x86/kvm/Kconfig"
  1754. source "lib/Kconfig"